Variable-speed gear.



No. 637,545. Patentedvnov. 26, 190|.

. A. smcLAm. A

VARIABLE SPEED GEAR.

(Application led Feb. 23. 1901.)

2 Sheets-Sheet I.

(No Model.)

[Hill l Patented Nov. 26, I90l.

A. SINCLAIR.

VARIABLE SPEEDVGEAB.

(Application led Feb 23, 1901 2 Sheets-Sheet 2.

(No Model.)

UNITED STATES PATENT Orrrc'n.

ARTHUR SINCLAIR, OF EDINBURGH, SCOTLAND, ASSIGNOR OF ONE-HALF TO ALEXANDER WOODOOOK MACKENZIE, OF EDINBURGH, SCOTLAND, "AND ROBERT PATERSON, OF GLASGOW, SCOTLAND.

VARIABLE-SPEED GEAR.

SPECIFICATION forming part of Letters Patent No. 687,546, dated November 26, 1901. Appnanttied February 23, '1901. serial No. 48.4.76. cromada To all whom t may concern..-V

Be it known that I, ARTHUR SINCLAIR, a subject offthe King of Great Britain and Ireland, and a resident of No. l0 Panmure Place, Edinburgh, Scotland, have invented new and useful Improvements in Variable-Speed Gear or Transmission Mechanism for Motor-Vehicles and other Machinery, of which the following is a specication.

This invention relates to improvements in variable-speed gear or transmission mechanism for motor-vehicles or for other machinery where such gear is required.

In carrying out my invention I employ two pulleys over and between which the drivingbelt passes, the arrangement being such that that part of the surface of the pulley which is in contact with the belt can be increased or decreased in diameter at the will of the attendant by simply operating a screw or equivalent gear, so that any desired ratio between the driving and driven pulleys, from their highest ratio to their lowest ratio, can be obtained.

For motor-vehicles driven by belt my invention is specially applicable, because one belt does the duty of the usual three belts as required for obtaining the usual three fixed varying speeds, so that not only does the one belt in accordance with my improvements do the duty of the three ordinary belts, but any desired intermediate speeds can be obtained, so that the engine `may always run at its normal speed, which is always desirable in motor-vehicles-that is to say, there is no necessity to reduce the firing when it is required to obtain a particular speed other 'than thatof the ordinary three xed speeds.

Each of the said pulleys consists of two coneshaped plates, oneot' which is fixed on the shaft, the other being capable of moving to and from the xed plate. Between these plates bars or dogs are arranged in such a manner that they can be moved from the cen ter or hub of the cone-shaped plates to near the periphery thereof, the said bars forming the varying-sized surface of the pulley for the belt to run on.

The accompanying drawings illustrate a mechanism applicable to a motorcar.

Figure I is aside elevation, and Fig. II is a plan of same, partly in section, showing the belt-bearing surface of the one pulley expanded to its largest diameter, the belt-bearing surface of the other pulley being shown contracted toits smallestdiameter. Figs. Ill, IV, V, VI, VII, and VIII are detail views, on a larger scale, illustrating the attachment of the dogs or bars to the coneshaped plates, as hereinafter described. Fig. IX is a detail view, partly in longitudinal section, illustrating a device for tightening or adjusting the belt. Fig. X is a plan of the pulley shown in sectional pian at the right-hand side of Fig..II.

The two cone-shaped plates A A4 form the sides of the one pulley. The plate A is keyed fast upon the shaft B, but the plate A4 is capable of moving to and from the said plate A upon the'shaftBby means of the clutch member T, Fig. X, formed on the cone-shaped plate, and the clutch-nut C, carried on the screw K, a key being provided on the shaft to take up the turning effect. According to the direction in which the screw K is turned by the handle L, Fig. II, the plate A@L is moved to or from the other plate A. By means of this movement the bars a2, which constitute the belt-bearing surface, are drawn out or in, so as to increase or decrease the diameter of the belt-bearing su rface. These motions may he edected during the rotation of the pulleys-that is to say, while the machine is running. 'Ihe arrangement and construction of the said moving bars a2 are as follows: Each of the plates A A4 and A2 A3 has a number of radial slots a, formed therethrough to receive the bars a2, which form the belt-bearing surface of the pulleys, the said bars being capable of sliding up and down in the said slots, being held in position in the man ner as shown in the enlarged detail views, Figs. III and IV, and in the modifications shown in Figs. V to VIII. Fig. III is a section through the coneshaped pulley-plate A, showing a bar a2 in position, and Fig. IV an end view of same. (See also the right-hand side of Fig. II.) The ends of the bars a2 are passed through the slots al in the cone-shaped pulley-plate, the protruding ends of the said bars being envel- ICO position between the two cone-shaped plates of each pulley, rivets a3 being passed through the two sides of the said U-shaped piece'a and through the projecting ends of the bars a2. As shown in Fig. Il and in enlarged detail, Fig. III, the bars are constructed with a shoulder or web a2, which bears as a guide against the other side of the cone-shaped plate A. The top part of the bar may be of a similar formation, as shown, in order to give the required bearing -surface for the belt. A simultaneous movementin the opposite direction is given to the cone-shaped plate A3, Fig. II, by means of the pivoted lever D, fulcrumed upon the pin N, carried bythe bracket F., Figs. I and II. The said plate A3 is provided with asimilar clutch to that described with reference to plate A4, except that an.

detail, Fig. IX.) The one end of the lever D is connected to the forked end G of the screw S by means of the pin H. The clutch member T of the cone-shaped plate AB is set at the required position on the shaft Bto or from the opposite cone-shaped plate A2 by means of the adjusting of the clutch-die C on the screw S and fixed by means of the adjusting-nuts J.

A collar R, Figs. II and IX, is preferably iixedon the shafts B and B- to prevent any movement of the pulleys when they have been expanded to their largest diameters, thus preventing any undue strain on the different parts of the mechanism.

Figs. V and VI show a modiiication in the means of mounting the bars a2, which consists in the employment of two rollers a4 on each side of the bar and which are secured in position by pins passing through the rollers and through the bar.

Figs. VII and VIII show a modification in which a set of rollers run on both sides of the cone-shaped plate.

lIn lieu of the screw K for operating the pulleys, as shown in the drawings, Imay employ any equivalent of the screw, such as a graduated quadrant and lever, the said quadrant and lever being arranged in any suitable position on the motor-car or machine to which the pulleys are applied.

-The particular framing as shown in the drawings is merely to illustrate the machine in which thepnlleys and gear operate, it

being obvious that the particular mode of mounting the gear will be in accordance with the kind of machine to which the invention is required to be applied.

Having thus described my invention, the following is what I claim as new and desire tosecnre by Letters Patent:

1. In a variable-speed-translnitting mechanism, the combination of a pair of coneshapedplates A Athavng radial slots a, mounted point to point on a shaft B, and capable of relative adjustment one toward or from the other; a series of parallel belt-bearing bars a2, guided by their ends in the radial slots a, and having near their ends bearing members which rest on the oblique faces of the cone-shaped plates A; and means for adjusting one of said cone-shaped plates toward or from the other, substantially as described.

2. The combination of two expansible pulleys, each consisting of a pair of radiallyslotted conical plates A A4; A2 A3;"and radially-movable belt-bearing bars a2; shafts B B onv which said pulleys are mounted; clutch members T T on the movable plates A4 A3, clutch-slides C C engaged therewith;.a connecting-lever D pivoted at its respective ends to the clutch-slides C and C to communicate reverse movement from one to the other; and a screw K for moving one of said clutchslides, substantially as set forth.

3. The combination of the paired radiallyslotted conical plates A A4 and A2 A3; radially-movable belt-bearing bars a2 mounted in the radial slots a of said plates; clutch niembers T T', slides C C connecting lever D and screw K for communicating simultaneous movement to thel plates A4 and A3; andthe adjustable connection G S J between the-lever D and slide C for imparting independent ICO adjustment to the plate A3, substantially as i and for the purposes explained.

' ARTHUR SINCLAIR.

Witnesses: v H. PEROY GIBBoNs MOREY,

DAVID R. MENZIEs. 

